Lighting is a necessary evil. Our circadian rhythm—the internal clock that controls our sleep-wake cycle—actually functions best when we're in nature, removed from artificial light altogether (it's why a weekend camping trip can help you get some zzz's).

But we can't all live by the light of the sun and moon, so we just need to be cautious about the type of light we surround ourselves with—especially at night and first thing in the morning. A general rule of thumb is that blue light is stimulating and energizing while warmer, yellow light is more relaxing. Turning on blue-light-emitting cellphones, TVs, and lamps right before bed, therefore, can throw off our internal clocks—which, by the way, control a lot more than just our sleep.

"It's not surprising that the drastic change in lifestyle and human social habits in the last 50 years have been linked to the rise in diseases like obesity, diabetes, sleep disorders, depression, and certain types of cancers, autism, and a variety of dementias, disorders that are likely associated with disturbances in the circadian rhythm," Eva Selhub, M.D., a Harvard-trained functional medicine doctor, recently wrote in an article on hacking your sleep cycles.

These six lamps and bulbs are all designed to support your body's inner clock by taking on different hues throughout the day and evening. Use them in tandem with other acts of good sleep hygiene and say lights out to restless nights.

1. Glow Light, Casper

The latest addition to the adult night-light scene is the just-released Glow Light by mattress company Casper. The brand's first foray into sleep accessories, the light was designed to help people wind down naturally. "Light influences our sleep-wake cycles, and even impacts our mood and ability to relax. While most lights keep us up, Glow is specifically designed to help us wind down naturally, for better, deeper sleep," Jeff Chapin, Casper co-founder and chief of product, tells mbg. The light gradually dims over 45 minutes to prime you for bed and brightens again in the morning to serve as an alarm-free wake-up call. It's also lightweight and portable for all you midnight snackers out there.

2. SceneSwitch, Philips

These LED bulbs by Philips have three settings: a white-blue light for daytime, a warm yellow light for nighttime, and an in-between hue. It's the basic, more affordable version of Philips' other high-tech bulbs, which can cover 16 million shades of color and pair with your phone and Alexa or Google virtual assistants.

3. A19 Smart Bulb, LIFX

This smart bulb is known for its incredible brightness. Like some of the Philips models, it also can take on millions of different colors and shades of white. You can program it to dim or change color at certain times of day, or adjust your settings manually using an app on your phone. If you have sticker shock, check out these mini versions of it at a lower price point.

4. Goodnight Bulb, Lighting Science

Originally developed for NASA astronauts in eternally dark space stations, this bulb filters out 95 percent of that blue light spectrum that gets in the way of our sleep. Lighting Science also offers Awake and Alert bulbs that have more blue light for your desk or any place you want to focus during the day.

5. Drift Light, Saffron

As the name suggests, the Drift Light becomes dimmer over a span of 37 minutes—meant to mirror the calming effect of a sunset. You can program it to either go completely dark or stop at "Moonlight Mode," which gives off a tiny bit of light and is ideal for a kid's room, bathroom, or hallway.

6. Relax HD, GE Lighting

GE’s HD LED series lets you set the tone in your home by customizing your lights based on what room they’ll go in. Relax HD offers a comfortable soft white light dimmable ideal for cozy spaces. All GE high definition bulbs are energy-saving LED’s and boost color and contrast.